Channel relay module is more or less the same as a single-channel relay module, but with some extra features like optical isolation. The dual-channel relay module can be used to switch mains powered loads from the pins of a Microcontroller.
3-Channel Relay Module With Optocoupler Isolation Compatible 3.3V 5V Signal
Power Supply Voltage:5V
Trigger Level:3V-7V trigger
Control Voltage:AC 0-250V or DC 0-30V